For electric tools having a pushing rod or an operating rod, in order to reduce volume during transportation and storage, the pushing rod or the operating rod is generally designed as two or more retractable sections. Therefore, a locking mechanism is needed to lock the relative position between the two sections of the pushing rod when stretching the pushing rod. Current locking mechanisms are located between a locking position and a releasing position, and cannot completely reach the locking position when the two sections of the pushing rod are retracted to the desired position. At that moment, the fastening force for the relative position between the two sections of the pushing rod is relatively small, therefore the pushing rod may be retracted during operation, which can affect the normal operation of the user.